The present invention relates to a device for sawing panels, particularly wooden panels, on panel sawing machines.
Panel sawing machines known up to the present time, in their minimum standard configurations, basically comprise: a horizontal table to support the stacks of panels to be cut; a gripper and handling unit designed to pick up the stack of panels at one end and feed it along a horizontal axis X towards the end of the table where there is a pressing device which holds down one end of the panel stack. In the area where the hold-down device is mounted, there is also a motor-driven carriage which mounts a circular saw and, in front of the latter, a scoring saw. The carriage moves in both directions along an axis Y transversal to the panel feed axis X, so as to allow the stack of panels to be scored on the surface and then cut through in the area where it is being held by the hold-down device. As is known, the scoring saw used in combination with the saw is designed to make only a shallow cut in the surface of the panel (usually the covering layer) in a direction such as to prevent surface splintering.
The higher production capacities of panel processing lines made possible by continuing technological improvements have greatly increased the demand for larger and larger quantities of panels cut to size to feed the panel processing lines. This demand has been met by simply using saw blades with larger and larger diameters so as to enable higher and higher stacks of panels to be cut.
This, however, has led to a number of practical disadvantages. Large circular saw blades bend more easily than smaller blades and consequently, offer lower cutting performance and the saw teeth are subject to more rapid wear. Another factor which determines the rapid wear of large blades is the high pressure exerted by the stacked panels on both sides of the blade in the area just cut (due to tension caused by the cooling of the material during the production cycle). The rapid wear of these large blades often results in macro-splintering (especially of the panel at the top of the stack) which requires additional machining to a considerable depth to smooth out the splintered surface of the stack just cut.
Moreover, these large circular saw blades are relatively slow-working, not entirely reliable in terms of technology and quality and expensive to run because they need high-powered motors to drive them and frequent sharpening operations.